Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752425AbaBMSKW (ORCPT ); Thu, 13 Feb 2014 13:10:22 -0500 Received: from mx1.redhat.com ([209.132.183.28]:46502 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752097AbaBMSKV (ORCPT ); Thu, 13 Feb 2014 13:10:21 -0500 Date: Thu, 13 Feb 2014 19:10:13 +0100 From: Oleg Nesterov To: Linus Torvalds Cc: Al Viro , Dave Chinner , Dave Jones , Eric Sandeen , Linux Kernel , xfs@oss.sgi.com Subject: Re: 3.14-rc2 XFS backtrace because irqs_disabled. Message-ID: <20140213181013.GA15596@redhat.com> References: <20140212040358.GA25327@redhat.com> <20140212042215.GN18016@ZenIV.linux.org.uk> <20140212054043.GB13997@dastard> <20140212113928.GO18016@ZenIV.linux.org.uk> <20140212211421.GP18016@ZenIV.linux.org.uk> <20140213174020.GA14455@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.18 (2008-05-17) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 02/13, Linus Torvalds wrote: > > On Thu, Feb 13, 2014 at 9:40 AM, Oleg Nesterov wrote: > > > > And we should be careful with SIGQUEUE_PREALLOC, at least > > collect_signal() should not do list_del_init()... Plus we need to > > handle the SEND_SIG_FORCED-like case. > > I don't think the users need to care. They'd just call > "sigqueue_free()" not knowing about our preallocations etc. Yes, but we need to be careful to avoid the races with release_posix_timer(). > That kind > of detail should be confined to inside signal.c. Yes, sure. > But there really aren't that many users. There's a couple of > "dequeue_signal_lock()" users, but they don't actually *want* the > siginfo at all (they're kernel threads), so we can just make that > function free the siginfo immediately (and get rid of the totally > unnecessay kernel stack allocation). Yes. Perhaps this helper should be changed/renamed. And perhaps we can even change __send_signal() to avoid __sigqueue_alloc() if PF_KTHREAD. Or sig == SIGKILL. Oleg. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/